/* Copyright 2021 The TensorFlow Authors. All Rights Reserved.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
==============================================================================*/

#include "tensorflow/lite/kernels/internal/reference/dequantize.h"

#include "tensorflow/lite/c/builtin_op_data.h"
#include "tensorflow/lite/c/common.h"
#include "tensorflow/lite/kernels/internal/quantization_util.h"
#include "tensorflow/lite/kernels/internal/reference/quantize.h"
#include "tensorflow/lite/kernels/internal/reference/requantize.h"
#include "tensorflow/lite/kernels/internal/tensor_ctypes.h"
#include "tensorflow/lite/kernels/kernel_util.h"
#include "tensorflow/lite/micro/kernels/dequantize.h"
#include "tensorflow/lite/micro/kernels/kernel_util.h"
#include "tensorflow/lite/micro/kernels/xtensa/xtensa.h"
#include "tensorflow/lite/micro/micro_log.h"

namespace tflite {

void* DequantizeInit(TfLiteContext* context, const char* buffer,
                     size_t length) {
  TFLITE_DCHECK(context->AllocatePersistentBuffer != nullptr);
  return context->AllocatePersistentBuffer(context, sizeof(DequantizeOpData));
}

TfLiteStatus DequantizeEval(TfLiteContext* context, TfLiteNode* node) {
  TFLITE_DCHECK(node->user_data != nullptr);
  DequantizeOpData* data = static_cast<DequantizeOpData*>(node->user_data);

  const TfLiteEvalTensor* input = tflite::micro::GetEvalInput(context, node, 0);
  TfLiteEvalTensor* output = tflite::micro::GetEvalOutput(context, node, 0);

  // Output type ensured to be kTfLiteFloat32 at the Prepare stage
  TFLITE_DCHECK(output->type == kTfLiteFloat32);

  switch (input->type) {
    case kTfLiteInt8: {
#if HIFI_VFPU && (defined(HIFI5) || defined(HIFI4) || defined(HIFI3))
      int err;
      const int8_t* input_data_ptr;
      float* output_data_ptr;
      const int flat_size =
          MatchingFlatSize(tflite::micro::GetTensorShape(input),
                           tflite::micro::GetTensorShape(output));
      input_data_ptr = tflite::micro::GetTensorData<int8_t>(input);
      output_data_ptr = tflite::micro::GetTensorData<float>(output);

      err = xa_nn_elm_dequantize_asym8s_f32(
          output_data_ptr, input_data_ptr, data->quantization_params.zero_point,
          data->quantization_params.scale, flat_size);
      TF_LITE_ENSURE(context, (err == 0));
#else   //  HIFI_VFPU && (defined(HIFI5) || defined(HIFI4) || defined(HIFI3))
      reference_ops::Dequantize(data->quantization_params,
                                tflite::micro::GetTensorShape(input),
                                tflite::micro::GetTensorData<int8_t>(input),
                                tflite::micro::GetTensorShape(output),
                                tflite::micro::GetTensorData<float>(output));
#endif  //  HIFI_VFPU && (defined(HIFI5) || defined(HIFI4) || defined(HIFI3))
      break;
    }
    case kTfLiteInt16: {
#if HIFI_VFPU && (defined(HIFI5) || defined(HIFI4) || defined(HIFI3))
      int err;
      const int16_t* input_data_ptr;
      float* output_data_ptr;
      const RuntimeShape& input_shape = tflite::micro::GetTensorShape(input);
      const RuntimeShape& output_shape = tflite::micro::GetTensorShape(output);
      const int flat_size = MatchingFlatSize(input_shape, output_shape);
      input_data_ptr = tflite::micro::GetTensorData<int16_t>(input);
      output_data_ptr = tflite::micro::GetTensorData<float>(output);
      err = xa_nn_elm_dequantize_asym16s_f32(
          output_data_ptr, input_data_ptr, data->quantization_params.zero_point,
          data->quantization_params.scale, flat_size);
      TF_LITE_ENSURE(context, (err == 0));
#else   // HIFI_VFPU && (defined(HIFI5) || defined(HIFI4) || defined(HIFI3))
      reference_ops::Dequantize(data->quantization_params,
                                tflite::micro::GetTensorShape(input),
                                tflite::micro::GetTensorData<int16_t>(input),
                                tflite::micro::GetTensorShape(output),
                                tflite::micro::GetTensorData<float>(output));
#endif  // HIFI_VFPU && (defined(HIFI5) || defined(HIFI4) || defined(HIFI3))
      break;
    }
    case kTfLiteUInt8:
      reference_ops::Dequantize(data->quantization_params,
                                tflite::micro::GetTensorShape(input),
                                tflite::micro::GetTensorData<uint8_t>(input),
                                tflite::micro::GetTensorShape(output),
                                tflite::micro::GetTensorData<float>(output));
      break;
    default:
      MicroPrintf("Input %s, output %s not supported.",
                  TfLiteTypeGetName(input->type),
                  TfLiteTypeGetName(output->type));
      return kTfLiteError;
  }

  return kTfLiteOk;
}

TFLMRegistration Register_DEQUANTIZE() {
  return tflite::micro::RegisterOp(DequantizeInit, DequantizePrepare,
                                   DequantizeEval);
}

}  // namespace tflite
